Computed Tomographic x-ray scanners (referred to herein as “CT scanners”) have been in clinical use since the early 1970s. Generally, a CT scanner uses a rotating x-ray beam and detector to make cross-sectional (or three-dimensional) images of human anatomy and other subjects. In prior CT scanners using flat panel detector arrays, the spatial resolution in the X-Y plane of the resulting image has been increased by angulating the detector array about the Z-axis, where the image is formed by rotating the object of the scan about a rotation axis S that is parallel to the Z-axis. This geometry is illustrated in FIGS. 1A-1B and 2A-2B, where FIGS. 1B and 2B depict the face of a detector array 18 viewed in the direction of the X-axis. In FIGS. 1A and 1B, the face of the detector array 18 is orthogonal to the X-axis (parallel to the Y-axis). In FIGS. 2A and 2B, the face of the detector array 18 is at an angle with respect to the X-axis and Y-axis. In this geometry, the axis about which the array 18 is angulated (also referred to herein as the VRX tilt axis) coincides with the Z-axis, and the axis of rotation of the object (also referred to herein as the scan axis S) is parallel to the Z-axis.
Although the CT scanner geometry depicted in FIGS. 2A and 2B provides the ability to increase image spatial resolution in the X-Y plane (scan plane), it does not provide any increase in spatial resolution in the Z-direction. What is needed, therefore, is a VRX-CT x-ray scanner having an improved geometry that provides for increased spatial resolution in the X-Y plane and the Z-direction simultaneously.